I don't know if you're misunderstanding eDPS or something, but if you're only getting 2.5M eDPS out Arcane Torrent with 1.3M sheet DPS, something is wrong. I have a bit over 800K buffed DPS and I'm getting about 14.5M eDPS with straight Cascade cast and Ignite Magic Weapon buff.
Armory | YouTube | Twitter | Clan Site